<?php

namespace think\controller;

use think\App;
use think\Request;
use think\Response;

abstract class Rest
{

  protected $method; // 当前请求类型
  protected $type; // 当前资源类型
  // 输出类型
  protected $restMethodList    = 'get|post|put|delete';
  protected $restDefaultMethod = 'get';
  protected $restTypeList      = 'html|xml|json|rss';
  protected $restDefaultType   = 'html';
  protected $restOutputType    = [ // REST允许输出的资源类型列表
    'xml'  => 'application/xml',
    'json' => 'application/json',
    'html' => 'text/html',
  ];

  /**
   * 架构函数 取得模板对象实例
   * @access public
   */
  public function __construct()
  {
    // 资源类型检测
    $request = Request::instance();
    $ext     = $request->ext();
    if ('' == $ext) {
      // 自动检测资源类型
      $this->type = $request->type();
    } elseif (!preg_match('/\(' . $this->restTypeList . '\)$/i', $ext)) {
      // 资源类型非法 则用默认资源类型访问
      $this->type = $this->restDefaultType;
    } else {
      $this->type = $ext;
    }
    // 请求方式检测
    $method = strtolower($request->method());
    if (false === stripos($this->restMethodList, $method)) {
      // 请求方式非法 则用默认请求方法
      $method = $this->restDefaultMethod;
    }
    $this->method = $method;
  }

  /**
   * REST 调用
   * @access public
   * @param string $method 方法名
   * @return mixed
   * @throws \Exception
   */
  public function _empty($method)
  {
    if (method_exists($this, $method . '_' . $this->method . '_' . $this->type)) {
      // RESTFul方法支持
      $fun = $method . '_' . $this->method . '_' . $this->type;
    } elseif ($this->method == $this->restDefaultMethod && method_exists($this, $method . '_' . $this->type)) {
      $fun = $method . '_' . $this->type;
    } elseif ($this->type == $this->restDefaultType && method_exists($this, $method . '_' . $this->method)) {
      $fun = $method . '_' . $this->method;
    }
    if (isset($fun)) {
      return App::invokeMethod([$this, $fun]);
    } else {
      // 抛出异常
      throw new \Exception('error action :' . $method);
    }
  }

  /**
   * 输出返回数据
   * @access protected
   * @param mixed     $data 要返回的数据
   * @param String    $type 返回类型 JSON XML
   * @param integer   $code HTTP状态码
   * @return Response
   */
  protected function response($data, $type = 'json', $code = 200)
  {
    return Response::create($data, $type)->code($code);
  }
}
